Refrigerating apparatus



y 1933- A. A. MOCORMACK 1,910,996

REFRI GERAT ING APPARATUS Filed Sept. 50, 1930 INVENTOR ATTORNEYS Patented May 23, 1933 UNITED STATES PATENT OFFICE ALEX A. MCGOBMACK, OF DAYTON, OHIO, ASSIGNOR TO FRIGIDAIBE CORPORATION, OF

DAYTON, OHIO, A CORPORATION OF DELAWARE REFRIGERATIN G APPARATUS Application filed September 30, 1930. Serial No. 485,382.

This invention relates to refrigerating apparatus and more particularly to mechanical refrigerating apparatus of the household type in which ice trays are provided for congealing comestibles which are often used for desserts or refreshments.

One of the objects of the invention is to provide in a refrigerating system having means for normally maintaining a normal predetermined temperature, a means for rendering such means ineffective when desired to maintain a lower temperature.

Another object of the invention is to provide a supplementary control means for a refrigerating system to control the system when the normal control means is rendered ineffective.

Another and more specific object of the in vention is to provide means in an intermittent compression refrigerating system to operate the compressor continuously when it is desired to congeal comestibles in ice trays within the coolingunit of the system.

A still further object of the invention is to maintain the cooling unit at a minimum temperature' during the time in which it is desired to congeal comestibles within the ice trays placed within the cooling unit.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing, wherein a preferred form of the present invention is clearly shown.

In the drawing:

The figure is a diagrammatic representation of a refrigerating system of the direct expansion type including a cooling unit containing ice trays therein positioned within the refrigerating cabinet.

Referring to the drawing, there is shown diagrammatically, for illustrative purposes, a refrigerating system of the compressorcondenser-direct expansion type, including a compressor 21 for compressing the refrigerant, preferably sulphur dioxide, and-for forwarding it to the condenser 22 where it is liquefied and collected in the receiver 23. A

supply conduit 26 sup'plies liquid refrigerant from the receiver 23 to the expansion valve 30 where the liquid refrigerant expands and passes into the cooling unit 27. The expanded refrigerant passes into the cooling unit 27 and first passes through a plurality of coilscomprising an inner ice freezing portion which extends about the ice trays 41 in which the comestibles are congealed. From the ice freezing portion of the cooling unit 27 the expanded refrigerant is conducted to the box cooling coils 42, which surrounds the inner tor circuit for providing alternating operating and idle periods of the compressor according to the temperature of the cooling unit 27. A frost back thermostatic switch 36 is also conected in series with the motor circuit for opening the circuit to stop the motor 24 and the compressor 21 when liquid refrigerant enters into the return conduit 28. The thermostatic bulb 37 is fastened to the return conduit 28 for this purpose and communicates with a bellows 38 for operating frigerant enters the return conduit 28 to prevent the frosting of the conduit and also to prevent liquid refrigerant from being re turned to the crankcase of the compressor 21.

According to the present invention means are provided for placing a shunt around the thermostatic switch 35' to render it ineffective when it is desired to quickly congeal comestibles within the ice trays 41. To this end a shunt having a hand operated switch 46 in series therewith is provided across the terminals of the thermostat switch 35 which normally controls the operation of the motor 24 and the compressor 21. The thermo- 35 which is connected in series with the mothis frost back switch 36 when the liquid restat switch 35-and the frost back switch 36 are in series with the motor circuit so that when the hand switch 46 is open,'the opening of eitherof the switches 35 or 36 stops the operation of the motor 24 or compressor 21. In normal operation the manually operable switch 46 remains open, the frost back switch 36 remains closed, and the thermostatically controlled switch 35 opens and closes to start and stop the motor 24 and the compressor 21 in response to the temperature conditions within the refrigerator cabinet 31 to maintain proper temperature therein. Should liquid refrigerant at any time, for any cause whatever, enter the return conduit 28 the frost back switch 36 will open stopping the motor 24 and the compressor 21 so that the liquid refrigerant is allowed to vaporize and is prevented from being returned to the compressor in liquid form, thereby avoiding frosting of the return con duit 28.

When it is desired to quickly congeal comestibles placed within the ice tray 21 the manually operable switch 46 is closed rendering ineffective the thermostatic switch 35 and causing the motor 24 and compressor 21 to operate continuously until liquid refrigerant floods the coils of the cooling unit 27 and enters the return conduit 28 to cause the frost back switch 36 to open and thus stop the motor and compressor. However, as soon as liquid refrigerant in the return conduit 28 has evaporated, the frost back switch 36 will automatically close and start the motor 24 and compressor 21. By this means it will be seen that when the manually operable switch 46 is closed the cooling unit 27 will be kept filled with liquid refrigerant and thus quick congealing of the comestibles placed within the ice trays 41 is assured.

\Vhile the form of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow. Y

What is claimed is as follows:

1. Refrigerating apparatus comprising in combination, a cooling unit, means for circulating a refrigerant through the cooling unit,

- means responsive to the temperature of said cooling unit for intermittently operating said circulating means to normally maintain the cooling unit at a substantially constant predetermined low temperature, manually actuated means for rendering said second named means ineffective and for causing said circulating means to operate continuously, irrespective of the temperature of the cooling unit, to produce a temperature in said cooling unit below said normal low temperature thereof, and means for automatically discontinuing the continuous operation of the circulating means, when said circulating means begins to withdraw liquid refrigerant from said cooling unit.

2. Refrigerating apparatus comprising in combination, acooling unit, means for circulating a refrigerant through the cooling unit, means responsive to the temperature of said cooling unit for intermittently operating said circulating means to normally maintain the cooling unit at a substantially constant predetermined low temperature, manually actuated means for rendering said second named means ineffective and for causing said circulating means to operate continuously, irrespective of the temperature of the cooling unit,'to produce a temperature in said cooling unit below said normal low temperature thereof, and means for automatically discontinuing the continuous operation of the circulating means after the accumulation of a predetermined amount of liquid refrigerant in said cooling unit.

3. Refrigerating apparatus comprising in combination, a cooling unit, means for circulating a refrigerant through the cooling unit, a conduit connecting the circulating means with the cooling unit, means responsive to the temperature of said cooling unit for intermittently operating said circulating means to normally maintain the cooling unit at asubstantially constant predetermined low temperature, manually actuated means for rendering said second named means ineffective and for causing said circulating means to operate continuously, irrespective of the temperature of the cooling unit, to produce a temperature in said cooling unit below said normal low temperature thereof, and means actuated automatically in response to the temperature within that portion of said conduit adjacent said cooling unit for discontinuing the continuous operation of said circulating means.

In testimony whereof I hereto aflix my signature. I

ALEX A. MCCORMAGK. 

